Re: [PATCH] 2.5.17 /dev/ports

[Martin Dalecki]

Uz.ytkownik Alan Cox napisa?:
>>Anybody: if you've ever used /dev/ports, holler _now_.
> 
> 
> Holler. I posted a list of examples to linux-kernel already. iopl and ioperm
> are not portable in the way /dev/port is. ioperm/iopl also doesnt work
> with most scripting languages, java tools trying to avoid JNI etc

What?

#include <linux/io.h>
#include <stdio.h>
#include <stdlib.h>

int main(char *argv[], int argc)
{
	int port = aoit(argv[0]);
	 int byte = aoit(argv[1]);

	if (port > 0)
		return inb(port);		
	 else
			outb(port, byte);

		return 0;
}

and then syscall("/sbin/doportio")

Is certainly *NOT IMPOSSIBLE*. But it's of course too
much of a burden...

BTW> Under java it's rather hard to get around
CAP_RAWIO if you ask me without going down to JNI.

> I've seen it used in tools written in java, python, perl, even tcl
> 
> Other examples include libieee1284, the pic 16x84 programmer, hwclock,
> older kbdrate, /sbin/clock on machines that don't have /dev/rtc.

All the examples above are samples of bad coding practice - I have
uncovered already here in C what can be expected inside there!

> Not everything in the world is an x86, and not every app wants to be Linux/x86
> specific or use weird syscalls

Yes and in esp. everything in the world is a __m68000__!